Make app looks good on mobile

[ydcjeff]

Clear and concise description of the problem

We are currently able to visit the site even on mobile, but it doesn't look good.

Suggested solution

Make app looks good with left sidebar and generated code in the middle.

Alternative

N/A

Additional context

[ydcjeff]

Is this GitHub bug? Not closing automatically?

[trsvchn]

Interesting...
but on the right we see:

Successfully merging a pull request may close this issue.

MAY close... :)) so
it's might be a bug)